qemu/win_dump.c

386 lines
11 KiB
C

/*
* Windows crashdump
*
* Copyright (c) 2018 Virtuozzo International GmbH
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qemu/cutils.h"
#include "elf.h"
#include "cpu.h"
#include "exec/hwaddr.h"
#include "monitor/monitor.h"
#include "sysemu/kvm.h"
#include "sysemu/dump.h"
#include "sysemu/sysemu.h"
#include "sysemu/memory_mapping.h"
#include "sysemu/cpus.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qemu/error-report.h"
#include "hw/misc/vmcoreinfo.h"
#include "win_dump.h"
static size_t write_run(WinDumpPhyMemRun64 *run, int fd, Error **errp)
{
void *buf;
uint64_t addr = run->BasePage << TARGET_PAGE_BITS;
uint64_t size = run->PageCount << TARGET_PAGE_BITS;
uint64_t len = size;
buf = cpu_physical_memory_map(addr, &len, false);
if (!buf) {
error_setg(errp, "win-dump: failed to map run");
return 0;
}
if (len != size) {
error_setg(errp, "win-dump: failed to map entire run");
len = 0;
goto out_unmap;
}
len = qemu_write_full(fd, buf, len);
if (len != size) {
error_setg(errp, QERR_IO_ERROR);
}
out_unmap:
cpu_physical_memory_unmap(buf, addr, false, len);
return len;
}
static void write_runs(DumpState *s, WinDumpHeader64 *h, Error **errp)
{
WinDumpPhyMemDesc64 *desc = &h->PhysicalMemoryBlock;
WinDumpPhyMemRun64 *run = desc->Run;
Error *local_err = NULL;
int i;
for (i = 0; i < desc->NumberOfRuns; i++) {
s->written_size += write_run(run + i, s->fd, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
}
static void patch_mm_pfn_database(WinDumpHeader64 *h, Error **errp)
{
if (cpu_memory_rw_debug(first_cpu,
h->KdDebuggerDataBlock + KDBG_MM_PFN_DATABASE_OFFSET64,
(uint8_t *)&h->PfnDatabase, sizeof(h->PfnDatabase), 0)) {
error_setg(errp, "win-dump: failed to read MmPfnDatabase");
return;
}
}
static void patch_bugcheck_data(WinDumpHeader64 *h, Error **errp)
{
uint64_t KiBugcheckData;
if (cpu_memory_rw_debug(first_cpu,
h->KdDebuggerDataBlock + KDBG_KI_BUGCHECK_DATA_OFFSET64,
(uint8_t *)&KiBugcheckData, sizeof(KiBugcheckData), 0)) {
error_setg(errp, "win-dump: failed to read KiBugcheckData");
return;
}
if (cpu_memory_rw_debug(first_cpu,
KiBugcheckData,
h->BugcheckData, sizeof(h->BugcheckData), 0)) {
error_setg(errp, "win-dump: failed to read bugcheck data");
return;
}
/*
* If BugcheckCode wasn't saved, we consider guest OS as alive.
*/
if (!h->BugcheckCode) {
h->BugcheckCode = LIVE_SYSTEM_DUMP;
}
}
/*
* This routine tries to correct mistakes in crashdump header.
*/
static void patch_header(WinDumpHeader64 *h)
{
Error *local_err = NULL;
h->RequiredDumpSpace = sizeof(WinDumpHeader64) +
(h->PhysicalMemoryBlock.NumberOfPages << TARGET_PAGE_BITS);
h->PhysicalMemoryBlock.unused = 0;
h->unused1 = 0;
patch_mm_pfn_database(h, &local_err);
if (local_err) {
warn_report_err(local_err);
local_err = NULL;
}
patch_bugcheck_data(h, &local_err);
if (local_err) {
warn_report_err(local_err);
}
}
static void check_header(WinDumpHeader64 *h, Error **errp)
{
const char Signature[] = "PAGE";
const char ValidDump[] = "DU64";
if (memcmp(h->Signature, Signature, sizeof(h->Signature))) {
error_setg(errp, "win-dump: invalid header, expected '%.4s',"
" got '%.4s'", Signature, h->Signature);
return;
}
if (memcmp(h->ValidDump, ValidDump, sizeof(h->ValidDump))) {
error_setg(errp, "win-dump: invalid header, expected '%.4s',"
" got '%.4s'", ValidDump, h->ValidDump);
return;
}
}
static void check_kdbg(WinDumpHeader64 *h, Error **errp)
{
const char OwnerTag[] = "KDBG";
char read_OwnerTag[4];
uint64_t KdDebuggerDataBlock = h->KdDebuggerDataBlock;
bool try_fallback = true;
try_again:
if (cpu_memory_rw_debug(first_cpu,
KdDebuggerDataBlock + KDBG_OWNER_TAG_OFFSET64,
(uint8_t *)&read_OwnerTag, sizeof(read_OwnerTag), 0)) {
error_setg(errp, "win-dump: failed to read OwnerTag");
return;
}
if (memcmp(read_OwnerTag, OwnerTag, sizeof(read_OwnerTag))) {
if (try_fallback) {
/*
* If attempt to use original KDBG failed
* (most likely because of its encryption),
* we try to use KDBG obtained by guest driver.
*/
KdDebuggerDataBlock = h->BugcheckParameter1;
try_fallback = false;
goto try_again;
} else {
error_setg(errp, "win-dump: invalid KDBG OwnerTag,"
" expected '%.4s', got '%.4s'",
OwnerTag, read_OwnerTag);
return;
}
}
h->KdDebuggerDataBlock = KdDebuggerDataBlock;
}
struct saved_context {
WinContext ctx;
uint64_t addr;
};
static void patch_and_save_context(WinDumpHeader64 *h,
struct saved_context *saved_ctx,
Error **errp)
{
uint64_t KiProcessorBlock;
uint16_t OffsetPrcbContext;
CPUState *cpu;
int i = 0;
if (cpu_memory_rw_debug(first_cpu,
h->KdDebuggerDataBlock + KDBG_KI_PROCESSOR_BLOCK_OFFSET64,
(uint8_t *)&KiProcessorBlock, sizeof(KiProcessorBlock), 0)) {
error_setg(errp, "win-dump: failed to read KiProcessorBlock");
return;
}
if (cpu_memory_rw_debug(first_cpu,
h->KdDebuggerDataBlock + KDBG_OFFSET_PRCB_CONTEXT_OFFSET64,
(uint8_t *)&OffsetPrcbContext, sizeof(OffsetPrcbContext), 0)) {
error_setg(errp, "win-dump: failed to read OffsetPrcbContext");
return;
}
CPU_FOREACH(cpu) {
X86CPU *x86_cpu = X86_CPU(cpu);
CPUX86State *env = &x86_cpu->env;
uint64_t Prcb;
uint64_t Context;
WinContext ctx;
if (cpu_memory_rw_debug(first_cpu,
KiProcessorBlock + i * sizeof(uint64_t),
(uint8_t *)&Prcb, sizeof(Prcb), 0)) {
error_setg(errp, "win-dump: failed to read"
" CPU #%d PRCB location", i);
return;
}
if (cpu_memory_rw_debug(first_cpu,
Prcb + OffsetPrcbContext,
(uint8_t *)&Context, sizeof(Context), 0)) {
error_setg(errp, "win-dump: failed to read"
" CPU #%d ContextFrame location", i);
return;
}
saved_ctx[i].addr = Context;
ctx = (WinContext){
.ContextFlags = WIN_CTX_ALL,
.MxCsr = env->mxcsr,
.SegEs = env->segs[0].selector,
.SegCs = env->segs[1].selector,
.SegSs = env->segs[2].selector,
.SegDs = env->segs[3].selector,
.SegFs = env->segs[4].selector,
.SegGs = env->segs[5].selector,
.EFlags = cpu_compute_eflags(env),
.Dr0 = env->dr[0],
.Dr1 = env->dr[1],
.Dr2 = env->dr[2],
.Dr3 = env->dr[3],
.Dr6 = env->dr[6],
.Dr7 = env->dr[7],
.Rax = env->regs[R_EAX],
.Rbx = env->regs[R_EBX],
.Rcx = env->regs[R_ECX],
.Rdx = env->regs[R_EDX],
.Rsp = env->regs[R_ESP],
.Rbp = env->regs[R_EBP],
.Rsi = env->regs[R_ESI],
.Rdi = env->regs[R_EDI],
.R8 = env->regs[8],
.R9 = env->regs[9],
.R10 = env->regs[10],
.R11 = env->regs[11],
.R12 = env->regs[12],
.R13 = env->regs[13],
.R14 = env->regs[14],
.R15 = env->regs[15],
.Rip = env->eip,
.FltSave = {
.MxCsr = env->mxcsr,
},
};
if (cpu_memory_rw_debug(first_cpu, Context,
(uint8_t *)&saved_ctx[i].ctx, sizeof(WinContext), 0)) {
error_setg(errp, "win-dump: failed to save CPU #%d context", i);
return;
}
if (cpu_memory_rw_debug(first_cpu, Context,
(uint8_t *)&ctx, sizeof(WinContext), 1)) {
error_setg(errp, "win-dump: failed to write CPU #%d context", i);
return;
}
i++;
}
}
static void restore_context(WinDumpHeader64 *h,
struct saved_context *saved_ctx)
{
int i;
Error *err = NULL;
for (i = 0; i < h->NumberProcessors; i++) {
if (cpu_memory_rw_debug(first_cpu, saved_ctx[i].addr,
(uint8_t *)&saved_ctx[i].ctx, sizeof(WinContext), 1)) {
error_setg(&err, "win-dump: failed to restore CPU #%d context", i);
warn_report_err(err);
}
}
}
void create_win_dump(DumpState *s, Error **errp)
{
WinDumpHeader64 *h = (WinDumpHeader64 *)(s->guest_note +
VMCOREINFO_ELF_NOTE_HDR_SIZE);
X86CPU *first_x86_cpu = X86_CPU(first_cpu);
uint64_t saved_cr3 = first_x86_cpu->env.cr[3];
struct saved_context *saved_ctx = NULL;
Error *local_err = NULL;
if (s->guest_note_size != sizeof(WinDumpHeader64) +
VMCOREINFO_ELF_NOTE_HDR_SIZE) {
error_setg(errp, "win-dump: invalid vmcoreinfo note size");
return;
}
check_header(h, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
/*
* Further access to kernel structures by virtual addresses
* should be made from system context.
*/
first_x86_cpu->env.cr[3] = h->DirectoryTableBase;
check_kdbg(h, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out_cr3;
}
patch_header(h);
saved_ctx = g_new(struct saved_context, h->NumberProcessors);
/*
* Always patch context because there is no way
* to determine if the system-saved context is valid
*/
patch_and_save_context(h, saved_ctx, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out_free;
}
s->total_size = h->RequiredDumpSpace;
s->written_size = qemu_write_full(s->fd, h, sizeof(*h));
if (s->written_size != sizeof(*h)) {
error_setg(errp, QERR_IO_ERROR);
goto out_restore;
}
write_runs(s, h, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out_restore;
}
out_restore:
restore_context(h, saved_ctx);
out_free:
g_free(saved_ctx);
out_cr3:
first_x86_cpu->env.cr[3] = saved_cr3;
return;
}